PORT CHARLOTTE, Fla. - The Mets' stellar pitching staff has endured its first casualty of the spring, with lefthanded reliever Josh Edgin announcing Sunday that he will undergo season-ending Tommy John surgery.

The Mets remain hopeful for a more encouraging report regarding starter Zack Wheeler, whose recent MRI exam was sent to New York for further review by team doctors.

Wheeler has soreness in his elbow, a condition that a year ago did not prevent him from logging a career-high 1851/3 innings.

But Edgin will be lost for a full year or more.

"It was the best decision for my future and my family," Edgin said in a statement. "The Mets stood behind me 100 percent. I'm disappointed, because we have a heck of a team. My mindset is to be ready to go on Opening Day, 2016."

Edgin's injury leaves a glaring weakness in the Mets' bullpen, though according to sources, the organization is confident that other options will become available at the end of spring training.

It's a period during which the player pool is replenished by players who are out of options but have failed to make a team, making them logical trade targets. Typically, veterans on minor-league deals that include out clauses also become available as free agents.

Sources said the Mets expect about a dozen of those types of players to be available. One player on the Mets' radar would be Dana Eveland, the 31-year-old lefty who pitched in New York last season. Last winter, Eveland signed a minor-league deal with the Red Sox, though he's not expected to break camp with the team. He also has an out clause in his contract that he can exercise before Opening Day.

Still, for the moment, the Mets seem more likely to stick with an internal candidate rather than reach for a veteran such as Eveland. None of the Mets' in-house arms have yet to distinguish themselves.

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"We'll continue to monitor how our internal candidates are doing and see what's available elsewhere," Alderson said. "We've got time during spring training to look at all possibilities and we'll do that."

As for Wheeler, 24, the Mets are awaiting results of a review of Saturday's MRI exam. Alderson said sending the results to New York were a matter of standard protocol.

In the meantime, Dillon Gee has been named the starter for Thursday, which would have been Wheeler's turn to pitch. Wheeler had already been scratched from a scheduled outing on Saturday.

Alderson downplayed the significance of the move calling it "somewhat independent of what's going on with Zack.' He said Wheeler could still pitch as scheduled, since the Mets are scheduled for split-squad games.

Said Alderson: "Right now it's just one start and we'll see where it goes from there."

Internally, the Mets don't seem worried about Wheeler's ailing elbow. But there is concern by some within the organization, including manager Terry Collins, that Wheeler's health could be an issue moving forward.

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